Ammonia Discharges to San Francisco Bay from Municipal Wastewater Treatment Plants

Regulators, scientists and the wastewater community are currently undertaking a series of studies to determine whether reductions in nutrients, including ammonia, are necessary to maintain health of the Bay. Wastewater treatment plants are the primary sources of anthropogenic nutrients in the Bay and this map shows the location of these plants and the relative scale of ammonia discharges, on a daily basis. This data was based on initial sampling efforts from 2012 collected by individual wastewater plants and available through the Regional Water Board. For questions please contact Ian Wren (

American Canyon City
Ammonia load: 1.2 kg/d Ammonia Concentration: 0.25 mg/L
Receiving water: North Slough
Data summary: single sample taken 1 July 2012